The present invention relates to the interface of a semiconductor device and, more specifically, to a semiconductor capable of easily adapting to interface conditions for a host application.
FIGS. 7A and 7B are plan views of important parts of semiconductor devices each of which is composed of a semiconductor integrated circuit device and a package that is mounted with the semiconductor integrated circuit device. In general, as shown in FIGS. 7A and 7B, electrode pads 92 on a semiconductor integrated circuit device 91 are arranged in the same order as lead terminals 93 which lead from a package 95. However, as for the interface with a host system to which this semiconductor device is to be connected, the arrangement order of the terminals may vary depending on the user for a reason on the host system side. This results in a problem in that semiconductor integrated circuit devices 91 cannot be made common in the case where they are manufactured so as to adapt to terminal arrangement orders of respective users as shown in FIGS. 7A and 7B.
Where semiconductor integrated circuit devices cannot be made common, the lead time and the cost that are taken in the development, including the evaluation of performance and reliability, of each semiconductor integrated circuit device are increased and the productivity is lowered because a flow with discrimination and procedure switching are needed on a manufacturing line. Furthermore, in recent years, semiconductor devices have come to be required to satisfy increased levels of requirements relating to EMC (electromagnetic compatibility) resistance (i.e., resistance to electromagnetic noise or a surge). Since the EMC resistance is very sensitive to the electrode pad arrangement and the wiring layout on a semiconductor integrated circuit device, designing for EMC is performed by repeating trial manufacture and evaluation of a device. Designing and developing semiconductor integrated circuit devices including designing for EMC for respective users who require different terminal arrangement orders is risky in terms of the lead time and the manufacturing cost.
On the other hand, as for the package shape, the current situation is such that commonization of packages is difficult because of a variety of requirements of users relating to the connector shape, the distance between connector terminals, and the package capacity (reduction). In view of this, a manufacturing method is employed in which a semiconductor integrated circuit device is formed on a small package called “cell package” having a common shape, its circuit characteristics are trimmed, and finally the common cell package is incorporated into an outer package having a shape that is desired by a user. This method makes it possible to commonize as many parts of manufacturing processes as possible and to thereby reduce the cost and the quality degradation. As such, this method can accommodate a wide variety of applications.
A specific conventional example, which is a semiconductor pressure sensor, will be described below with reference to FIGS. 8A and 8B. FIG. 8A is a schematic plan view of a pressure sensor cell and FIG. 8B is a schematic sectional view taken along line A-A in FIG. 8A. A pressure sensor cell 80 of FIGS. 8A and 8B is an exemplary sensor which is used in an engine intake manifold, for example. A Wheatstone bridge (not shown) having four piezoresistance elements which converts pressure into strain, a power electrode pad (not shown) for introduction of power from the outside, and a ground potential electrode pad (not shown) for introduction of a ground potential from the outside are formed on a semiconductor integrated circuit device 12. An output signal of the Wheatstone bridge is amplified by an amplifier circuit (not shown) which is incorporated in the semiconductor integrated circuit device 12, and the amplified signal can be output from the device via an output electrode pad (not shown) for output of a sensor signal which is also formed on the semiconductor integrated circuit device 12. Trimming electrode pads (not shown) for input/output of signals for trimming the characteristics of the above-mentioned amplifier circuit etc. are also formed on the semiconductor integrated circuit device 12. The semiconductor integrated circuit device 12 is bonded to a glass seat 13 by anodic bonding, and they thus constitute a pressure detecting element 10. The pressure detecting element 10 is fixed to, with an adhesive, and contained in a resin cell package 20 which incorporates, as a result of insert molding, a power lead terminal 21 for introduction of power from the outside, a ground potential lead terminal 23 for introduction of a ground potential from the outside, an output lead terminal 22 for output of a sensor signal to the outside, and circuit characteristics trimming lead terminals 24. The power electrode pad, the ground potential electrode pad, the output electrode pad, and the trimming electrode pads of the semiconductor integrated circuit device 12 are connected to the power lead terminal 21, ground potential lead terminal 23, the output lead terminal 22, and the trimming lead terminals 24 of the resin cell package 20, respectively, via Al or Au bonding wires 26. A gel member 27 is charged so as to protect the pressure detecting element 10 and the bonding wires 26. In FIGS. 8A and 8B, the trimming lead terminals 24 are drawn so as to have shapes that are obtained after cutting. In the pressure sensor device, the trimming lead terminals 24 are cut after trimming the circuit characteristics because they are no longer necessary during operation. The pressure sensor cell 80 is mounted on an outer package 40 shown in FIGS. 9A and 9B and electrically connected to the outside via connector terminals 45-47.
FIG. 9A is a schematic plan view of a pressure sensor device and FIG. 9B is a schematic sectional view taken along line B-B in FIG. 9A. The pressure sensor cell 80 of FIGS. 8A and 8B is incorporated in the outer package 40 having a power contact electrode 41, a sensor output contact electrode 42, and a ground potential contact electrode 43. The power lead terminal 21, the ground potential lead terminal 23, the output lead terminal 22 are welded to the power contact electrode 41, the ground potential contact electrode 43, and the sensor output contact electrode 42, respectively. The outer package 40 is closed tightly by a cap (not shown).
In the above conventional example, the arrangement order of the electrode pads on the semiconductor integrated circuit device 12 is the same as that of the power lead terminal 21, the output lead terminal 22, and the ground potential lead terminal 23 of the pressure sensor cell 80. In the outer package 40 which incorporates the pressure sensor cell 80, the arrangement order of the connector terminals 45-47 are the same as the electrode pads on the semiconductor integrated circuit device 12. Therefore, when the terminal arrangement order of the connector receiving side of a host system is changed, a new semiconductor integrated circuit device 12 is designed in which the arrangement order of its electrode pads is changed or crossed wiring is employed in connecting means which connect the semiconductor integrated circuit device 12 to the lead terminals 21-23 of the pressure sensor cell 80.
Alternatively, the terminal arrangement order is converted by modifying the lead terminals 21-23 and adjusting their wire bonding connecting positions to the electrode pads on the semiconductor integrated circuit device 12. For example, JP-A-6-186104 (FIGS. 6 and 7) discloses a technique relating to wire bonding between the bonding pads on a semiconductor pressure sensor device and a lead frame of a package. The arrangement order of lead terminals leading from the package is converted by elongating parts of inner leads of the lead frame of the package and adjusting the inner-lead-side wire bonding positions. In U.S. Pat. No. 6,833,608 (corresponds to JP-A-2003-152009 (FIG. 3)), the terminal arrangement order is switched by preparing at least two conductor patterns on an insulative support substrate and adjusting the wire bonding positions in making connections to a semiconductor device.
Where bonding wires are crossed or the bonding positions are changed as in the conventional examples, variations occurs in the wire loop lengths and the angles of wire neck portions, which may cause trouble such as short-circuiting between wires or disconnection of a wire. In particular, such trouble is remarkable in devices such as vehicular pressure sensors in which wires are protected only by a soft member such as a gel member and which are used in a vibratory environment.
In a manufacturing process, changing the bonding positions requires procedure switching and determination of bonding conditions for keeping the bonding wires reliable, but this adversely affects the productivity. Furthermore, in cell packages such as the pressure sensor cell 80 having a semiconductor integrated circuit device and lead terminals, trimming may be performed to correct its characteristics after assembling into a package. In general, trimming is performed by monitoring an output characteristic while supplying power by connecting a probe or a socket to the lead terminals which lead from the resin cell package. Where the terminal arrangement is changed by changing the manner of wire bonding in the above-described manner, also the arrangement of the terminals of the probe or socket on the trimming apparatus side need to be changed each time according to the specification of the arrangement of the lead terminals of the cell package. This results in losses due to modification of the trimming apparatus and procedure switching at the time of manufacture.